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<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
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  <title>Document</title>
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<body>
  <script src="./my.js">
    //中间不要写内容，会被忽略
    //外部JavaScript会使代码更加有序，更易于复用，且没有脚本混合，HTML也会更加容易读
    //因此，这样算是好习惯
  </script>
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